The present invention relates to a connecting structure for an optical conductor tube which transmits light energy.
The present applicant has previously proposed various ways for guiding solar rays focused by a lens or the like into an optical conductor for transmitting solar rays therethrough onto an optional desired place for use in illumination or for other purposes. However, in general, an optical conductor cable is used for conducting the light rays and it is very expensive. Therefore, in order to lower the cost thereof, an optical conductor rod (a quartz rod) was chosen. The optimal length of the optical conductor rod is about 4 m in consideration of transportability and operating efficiency. In practice it is necessary to employ a plurality of optical conductor rods connected with each other. Usually the outer surface of optical conductor rods are not protected or coated. For this reason the outer surface thereof is apt to get damaged and therefore light rays tend to leak from the damaged portion of the optical conductor rod. Also if dust or the like are allowed to be on the outer surface of the optical conductor rod, light rays leak therefrom. In this case the optical conductor rod is protected by means of a pipe or the like for preventing light rays from leaking therefrom.
However, in practice, a solar ray collecting device is installed on the rooftop of a building and solar rays focused by a solar ray collecting device are guided through an optical conductor tube having an optical conductor rod protected by a pipe onto each floor of the building or to an underground area. On that occasion, it is necessary to connect a large number of optical conductor tubes vertically and in cascade fashion and the optical conductor rod in the pipe is apt to slide down in the pipe by the sheer weight thereof.